Precious-metal alloy.



RUDOLPH JOHN PESGHKO, 01F YORK, PENNSYLVANIA.

I PRECIOUS-METAL ALLOY.

imitates.

l lo Drawing.

To all whom it may concern:

Be it known that I, RUDOLPH JOHN.

Pnscrnro, a citizen'of the United States, re-

siding in York, county of York, State of" Pennsylvania, have invented a Precious- Metal Alloy, of which the following isv a specification.

My invention relates to alloys particularly designed for use as substitutes for platinum in the manufactureof jewelry, scientific instruments, dental supplies and electrical apparatus, one object being to provide alloys which while cheaper than'platinum shall not be inferior to it for the purposes noted, as regards certain of their qualities.

It is further desired to provide alloys which, with possible exception of those COD? 'taining from 70% to 80% of gold, shall possess a color such as will render them indistinguishable from platinum, it being particularly desired that said alloys be relatively soft, easily workable, shall possess a tensile strength higher than that of platinum, shall becapable of receiving a high polish, and shall have wearing qualities practically equal to those of platinum.

'lln carrying out my invention l[ fuse together platinum, palladium, and gold, and while the proportions of these metals may -be considerably varied without departing from my invention, in a typical case I employ particularly for dental supplies, an alloy containing 10 parts of platinum, 30

Specification of Letters fatent.

Application filed March 12, 1915 Serial No. 13,897.

Patented Jan. 25, Mitt.

to 2%, it being noted that one of these hardening metals may be used alone or several of them together may be employed.

For the purpose of making the alloy, an oxy-gas flame or an electric'furnace may be employed, with a lime, magnesium or graphite crucible, although the actual method of procedure in combining the metals constitutng my alloy'forms no part of the present Invention.v

It is to be noted that all of the above described alloys are ractically insoluble in mineral and organic acids, with the possible exception of the high silver allows which. are

slowly-attacked by nitric acid'andboiling sulfuric acid. All of the alloys are soluble in aqua regia. A valuable feature of the alloys resides in the fact thatv they do not discolor or oxidize in air at temperatures below their melting points and will in every case take a high polish equal or superior to that characterizing platinum.

I claim 1. An alloy containing 10 parts of platinufi, 30 parts of palladium and 60 parts of go 2. An alloy containing platinum, palladium, gold and a metal having the property of increasing the tensile strength of the alloy, the gold being in excess.

3. An alloy containing platinum, palladium, and an excess of gold.

4. An alloy containing platinum, palla dium, and an excess of gold, with from to 2% of a hardening metal.

5. An alloy containing platinum, palladium, and an excess of gold, with from to 2% of iridium.

In testimony whereof I have -signed my name to this specification in the presence of two subscribing witnesses.

RUDOLPH JOHN rnsco.

Witnesses A. B. Samar, EDWARD J. LOUCKS. 

